Dr. Choan Choun E – Oncologist / Hematologist | Ottawa, ON

Dr. Choan Choun E, a Radiation Oncologist, utilizes advanced radiation therapies to treat various forms of cancer, working as part of a multidisciplinary team. Practicing at GI Division in Ottawa, ON, he is part of a dedicated healthcare team committed to providing comprehensive cancer care. His practice is guided by the standards and ethical practices established by the College of Physicians and Surgeons of Ontario (CPSO). Dr. E's expertise includes the precise planning and delivery of radiation therapy for a variety of cancer types, ensuring individualized treatment approaches tailored to each patient’s unique condition. He primarily serves adult patients with suspected or diagnosed cancer or blood disorders, leveraging access to state-of-the-art diagnostic and treatment facilities to optimize patient outcomes.

Dr. E graduated with a Medical Degree from the University of Toronto in 1993 and has been practicing as a Radiation Oncologist for over 26 years since 1998. He is certified as a RCPSC Specialist in Radiation Oncology, demonstrating his specialized training and commitment to excellence in cancer treatment with radiation. His extensive experience allows him to stay at the forefront of evolving therapies and innovative treatment techniques, ensuring patients benefit from the latest advances in the field.

Dr. E is dedicated to providing patient-centered, evidence-based care with a focus on multidisciplinary collaboration, research, and continuous improvement. He is committed to supporting his patients and their families through compassionate care, clear communication, and shared decision-making. Fluent in English, Dr. E actively engages with his patients to ensure they understand their treatment options and feel supported throughout their cancer journey.

Dr. Choan E has expertise in managing a wide range of conditions, including:

Hematologic Malignancies (Blood Cancers) Treated

• Multiple Myeloma: A cancer of plasma cells, a type of white blood cell in the bone marrow that produces antibodies, leading to bone damage and other complications.
• Myelodysplastic Syndromes (MDS): A group of diverse bone marrow disorders in which the bone marrow does not produce enough healthy, mature blood cells.
• Hodgkin Lymphoma: A cancer of the lymphatic system, part of the immune system, characterized by the presence of Reed-Sternberg cells.

Common Cancers (Solid Tumors) Treated

• Brain & Central Nervous System (CNS) Tumors (Primary & Metastatic - Medical Oncology aspects): Malignant tumors of the brain and spinal cord, where medical oncologists may manage chemotherapy or targeted therapies as part of a multidisciplinary team.
• Ovarian, Uterine (Endometrial), & Cervical Cancers (Gynecologic Oncology - Medical Aspects): Systemic treatment aspects for cancers of the female reproductive system, often in collaboration with gynecologic oncologists or surgeons.
• Breast Cancer (Early Stage, Locally Advanced, Metastatic): Malignant tumors developing in the cells of the breast, managed with various therapies including hormonal, chemo, targeted agents, and immunotherapy.

Common Areas/Cancers Treated with Radiation Oncology

• Thoracic Cancers (e.g., Lung Cancer, Esophageal Cancer, Mesothelioma): Using radiation therapy to treat cancers within the chest cavity, often combined with other modalities.
• Central Nervous System (CNS) Tumors (Brain & Spine): Employing precise radiation techniques to treat benign and malignant tumors of the brain and spinal cord.
• Genitourinary Cancers (e.g., Prostate, Bladder, Testicular): Using radiation therapy, including brachytherapy for prostate cancer, to treat cancers of the male and female urinary and reproductive systems.

This list provides examples of common conditions treated and is not exhaustive. Cancer and blood disorders are complex, and treatment is highly individualized. For personalized advice, please discuss your specific situation with Dr. Choan E or your referring physician.

• Radiation Therapy Consultation & Treatment Planning: Comprehensive assessment to determine if radiation therapy is an appropriate treatment modality, followed by meticulous 3D/4D simulation and treatment planning.
• Image-Guided Radiation Therapy (IGRT): Utilizing advanced imaging during treatment delivery to precisely target tumors and adapt to changes, while minimizing exposure to healthy tissues.
• External Beam Radiation Therapy (EBRT) - 3D Conformal, IMRT, VMAT: Developing precise, individualized plans for delivering radiation using external machines (e.g., linear accelerators) with techniques like Intensity-Modulated Radiation Therapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT).
• Total Body Irradiation (TBI) - Component of Stem Cell Transplant Regimens: Radiation therapy delivered to the entire body, often used as part of the conditioning regimen before a bone marrow or stem cell transplant.
• Palliative Radiation Therapy for Symptom Control: Using radiation to alleviate pain, bleeding, or obstruction caused by cancer.
• Prophylactic Cranial Irradiation (PCI): Preventative radiation treatment to the brain for certain cancers at high risk of brain metastases.
• Genetic Counseling & Testing Referrals for Hereditary Cancer Syndromes: Assessment of family history and risk factors, and coordination of referrals for genetic counseling and testing for inherited predispositions to cancer (e.g., BRCA).

Note: This list provides a general overview of services offered in Radiation Oncology (Cancer Treatment with Radiation). Treatment plans are highly individualized. Dr. E provides a wide array of diagnostic, therapeutic, and supportive care options tailored to each patient's specific condition and needs. Please discuss with Dr. E or your healthcare team for details relevant to your care.

All medical services and treatments are provided in accordance with the standards of practice set by the College of Physicians and Surgeons of Ontario (CPSO) and relevant cancer care guidelines. A referral is required.

The GI Division practice is located in the Overbrook, Castle Heights, Vanier South neighbourhood of Ottawa. The facility is centrally situated near landmarks such as Lansdowne Park (TD Place Stadium/Arena) and the Glebe Shopping District, making it a convenient choice for patients in the region. Public transit options include OC Transpo services, including the O-Train LRT and bus routes, providing easy access for patients. The location is fully wheelchair accessible to accommodate all patients, and metered street parking is available nearby for those arriving by car. The practice's strategic location ensures that patients can access comprehensive cancer care with ease and comfort.

Are consultations and treatments with Dr. E, an Radiation Oncologist, covered by Ontario Health Insurance Plan (OHIP) in ON?

Medically necessary consultations, diagnostic tests (like biopsies, imaging reviews), chemotherapy, immunotherapy, targeted therapies, radiation therapy planning and delivery, and management of blood disorders by a licensed Radiation Oncologist such as Dr. E are generally covered by Ontario Health Insurance Plan (OHIP) in ON when a referral from a family doctor or another specialist is in place. Specific drug coverage for newer therapies can vary by provincial formularies and may require special authorization. It's always recommended to discuss coverage specifics with Ontario Health Insurance Plan (OHIP), Dr. E's office, the hospital's patient financial services, or the cancer care navigation services at the treatment facility.

Do I need a referral to see Dr. E, an Radiation Oncologist?

Yes, a referral from your family physician or another specialist is almost always required to see an Radiation Oncologist like Dr. E for assessment or treatment of cancer or significant hematological conditions. This ensures that your primary care provider is involved in your care continuum and that you are directed to the most appropriate specialist for your specific situation. Cancer care programs often have centralized intake systems that manage referrals to ensure timely access.

How will treatment decisions be made for my condition by Dr. E?

Treatment decisions in oncology and hematology are highly personalized and made collaboratively. Dr. E will consider many factors, including the type and stage of your cancer or blood disorder, your overall health, genetic markers of the disease (if applicable), current treatment guidelines, and importantly, your personal preferences and values. Often, cases are discussed in multidisciplinary team meetings (tumor boards) with other specialists to ensure a comprehensive approach. You will be an active participant in this decision-making process.

What is palliative care, and when might Dr. E discuss it?

Palliative care is specialized medical care focused on providing relief from the symptoms and stress of a serious illness, like cancer or advanced blood disorders. The goal is to improve quality of life for both the patient and the family. It can be provided at any stage of illness, alongside curative treatments, not just at the end of life. Dr. E may discuss palliative care if you are experiencing significant symptoms, to help manage pain, fatigue, nausea, anxiety, or other issues, and to provide an extra layer of support.

Does a Hematologist only treat blood cancers?

No, Hematologists treat a wide range of blood disorders, not just cancers. This includes benign (non-cancerous) conditions such as various types of anemia (e.g., iron deficiency anemia, vitamin B12 deficiency, sickle cell anemia, thalassemia), bleeding disorders (like hemophilia or von Willebrand disease), clotting disorders (thrombophilia, deep vein thrombosis, pulmonary embolism), and issues with white blood cells (like neutropenia) or platelets (like ITP). Dr. E, if focused on hematology, can diagnose and manage these conditions.

What is Radiation Oncology and when is it used?

Radiation Oncology is a medical specialty that uses high-energy radiation (like X-rays, gamma rays, or charged particles) to damage or destroy cancer cells and shrink tumors. It can be used as a primary treatment, before surgery (neoadjuvant), after surgery (adjuvant), or in combination with chemotherapy. It can also be used for palliative care to relieve symptoms. Dr. E specializes in planning and delivering radiation therapy using techniques like EBRT, IMRT, SBRT, or brachytherapy. If you have a cancer that is best treated with radiation, Dr. E will develop a personalized treatment plan to effectively target your tumor while preserving healthy tissue.

How is cancer care typically coordinated when seeing Dr. E?

Cancer care and complex hematology care often involve a multidisciplinary team (MDT) of specialists working together. This team may include medical oncologists like Dr. E, surgeons, radiation oncologists, pathologists, radiologists, specialized oncology nurses, pharmacists, social workers, dietitians, genetic counselors, and palliative care specialists. Regular team meetings (often called tumor boards or MDT meetings) usually occur to discuss individual patient cases and develop comprehensive, coordinated treatment plans. Dr. E works collaboratively within this team to ensure you receive holistic and well-managed care.

GI Division
532 Montréal Road, Kingston HSC-Hotel Dieu Hospital
Ottawa, ON K1K 4R4

Phone: (613) 680-8777 | Fax: (613) 680-8599

The facility is wheelchair accessible.

Dr. E is a licensed Radiation Oncologist regulated by the College of Physicians and Surgeons of Ontario (CPSO) under the Regulated Health Professions Act, 1991 and Medicine Act, 1991 in ON. A referral from a family physician or other specialist is required for most consultations and treatments under the provincial health plan.

Verify registration with the College of Physicians and Surgeons of Ontario (CPSO): https://doctors.cpso.on.ca/DoctorDetails/E-Choan-Choun/0052849-66813